1. Field of the Invention
The present invention relates to the antagonistic bacteria that can be used to prevent and eliminate the bacterial wilt of continuous cropping tobacco and their microbial organic fertilizer, which belong to the technology for agricultural intensive production and is exclusively used to overcome and eliminate the bacterial wilt of continuous cropping tobacco.
2. Description of the Related Art
Tobacco is the main economic crop in China, and its quality is related to the national economy and people's livelihood. Tobacco bacterial wilt is one of the major diseases of tobacco, which does serious harm and is called “cancer of tobacco”. It was first found in the USA in 1880. Currently, it universally occurs in the tobacco producing areas in Southwest China and is often in a form of outbreak epidemic in the affected areas, resulting in devastating loss and about 80% of loss of yield in serious cases. Tobacco bacterial wilt is a serious soilborne bacterial disease. It is widely distributed in the tropical zone, subtropical zone and some warm areas in the world. In China, the disease occurs universally in Henan, Shandong, Jiangsu, Yunnan, Guangxi, Hebei, Hunan, Guangdong and Fujian and becomes one of the reasons for the decline of Chinese tobacco yield and quality. The pathogen of tobacco bacterial wilt (Ralstonia solanacearum) can be spread through soil, flowing water (for example, irrigation), seeds and other means and is highly adaptable to the environment. In the early stage of the infection of Ralstonia solanacearum to soil, as its quantity is small, the plants have the following symptoms: the growth is restricted and the plants are short, small, malformed and susceptible. Farmers often consider the symptoms as a problem of lacking nutrient and thus apply more nitrogen fertilizer. Consequently, the imbalance of the microfloras in the soil is from bad to worse, and the pathogen occupies a dominant position in rhizosphere, thus tobacco bacterial wilt occurs. Under the condition of high temperature and high humidity, the disease develops rapidly, and the morbidity in the fields with serious attack of the disease is 100%, resulting in no harvest.
On the other hand, the straw of paddy, wheat, corn, rape and other crops is burned on the spot and the excrement of the livestock and poultry raised on a scale is discarded. It not only seriously pollutes environment but also is a great waste of the raw material that can be used to produce organic fertilizer and bio-organic fertilizer products; enormous nutritive resources (C, N, P, K, S and trace elements) are lost outside the soil—plant system and the capability of sustainable development of Chinese agriculture is obviously weakened. How to maximally return the nutritive elements taken away from soil due to harvesting of crops to the soil? The only way is to make these solid organic wastes into commercial organic fertilizer and apply the fertilizer to the soil. If these solid organic wastes are synthesized into high-grade organic compost through high-temperature fermentation and then the compost is used as a carrier of functional bacteria to prepare microbial organic fertilizer, the function will be clear and there will be a good application prospect.